In the oil and gas industry, a well that is not producing as expected may need stimulation to increase the production of subsurface hydrocarbon deposits, such as oil and natural gas. Hydraulic fracturing has long been used as a major technique for well stimulation. The rapid development of unconventional resources in recent years has led to a renewed interest in hydraulic fracturing, and particularly multistage hydraulic fracturing. Examples of such unconventional resources include, but are not limited to, oil and/or natural gas trapped within tight sand, shale, or other type of impermeable rock formation. A multistage hydraulic fracturing operation may involve drilling a number of parallel horizontal wellbores and applying a series of stimulation injections along each wellbore in multiple stages. Two critical parameters affecting the success of a multistage hydraulic fracturing design are (1) the distance between the stages of a multistage horizontal well stimulation (or “stage interval”) and (2) the distance between neighboring horizontal wells (or “well spacing”). A proper choice of values for each of these two parameters may have a significant impact on the extent to which production of an unconventional resource is increased during the multistage hydraulic fracturing operation.
Conventional approaches to stage interval design for multistage hydraulic fracturing are generally based on the analysis of fracture propagation through reservoir rock using a pseudo three-dimensional (3D) fracture model. For example, various software application tools are available for performing fracture simulation and analysis using 3D planar fracture models. The outputs of such fracture simulation tools mainly include the length and height of the 3D planar fracture. However, these tools provide very little information with respect to the lateral effects of the fracture propagation. Other approaches, such as the commonly known “stress shadow method,” analyze the stress distribution around a particular facture or crack within a rock formation under a given fluid pressure at crack surfaces. However, this type of analysis fails to provide any useful information regarding fracture propagation under hydraulic fracturing. Therefore, this method does not provide accurate information about the effects of the fracture propagation. Accordingly, conventional approaches, such as the stress shadow method, provide only a rough approximation of stage interval values.